Dental implant with an interface that connects a porous bone fixation body to a metal coronal body

Abstract

A dental implant has a coronal body formed of solid metal that connects at an interface to a bone fixation body. The bone fixation body is made separately from the coronal body and has a porous structure with a cylindrical shape. The bone fixation body connects to the coronal body after the bone fixation body is separately made from the coronal body.

What is claimed is: 
     
       1. A method, comprising:
 machining a coronal body of a dental implant from solid metal to have a cylindrical configuration with a proximal end surface having an internal polygonal connection that connects to a dental component, with a distal end surface, and with an elongated cylindrical protrusion that extends outwardly from the distal end surface and includes a polygonal external shape in a side-view of the coronal body; 
 fabricating, separately from the coronal body, a bone fixation body of the dental implant that has a cylindrical shape from a side-view of the bone fixation body and is formed of a porous metal structure without a metal substrate but with the porous metal structure that extends throughout the bone fixation body such that the porous metal structure includes interconnected interstitial pores including a porosity of 45% to 65% with a geometric configuration that encourages natural bone to migrate and grow into and throughout the porous metal structure; and 
 connecting, after the bone fixation body is separately fabricated from the coronal body to have the cylindrical shape from the side-view, the bone fixation body to the coronal body to form the dental implant, the bone fixation body and the coronal body connecting at an interface where a proximal end surface of the bone fixation body abuts the distal end surface of the coronal body and where the elongated cylindrical protrusion of the coronal body extends into and engages the bone fixation body such that the bone fixation body surrounds and abuts the polygonal external shape of the elongated cylindrical protrusion in order to increase the interface between the coronal body and the bone fixation body. 
 
     
     
       2. The method of  claim 1 , wherein the porous metal structure has a size and a shape of a porous structure of natural bone. 
     
     
       3. The method of  claim 1 , wherein the elongated cylindrical protrusion of the coronal body has a non-tapering cylindrical shape. 
     
     
       4. The method of  claim 1 , wherein the dental implant includes three different regions of a smooth outer surface at a proximal end on the coronal body, the porous metal structure of the bone fixation body, and a non-porous bone engaging surface on the coronal body that is intermediate the smooth outer surface and the porous metal structure of the bone fixation body. 
     
     
       5. The method of  claim 1 , wherein the bone fixation body is bonded to the coronal body after the bone fixation body is separately formed from the coronal body. 
     
     
       6. The method of  claim 1 , wherein the cylindrical shape of the bone fixation body tapers in the side-view of the bone fixation body. 
     
     
       7. The method of  claim 1 , wherein the coronal body from the proximal end surface to the distal end surface has a non-tapering cylindrical shape in the side-view of the coronal body.